Laser-assisted Cataract Surgery Group Research Articles

Comparison of pupillary diameter variation between conventional phacoemulsification versus femtosecond laser-assisted cataract surgery

Purpose: To evaluate and compare variations in pupillary diameter before and after cataract surgery by conventional phacoemulsification versus femtosecond laser assisted cataract surgery, using LDV Z8 (Ziemer Ophthalmic). We also evaluated the relationship between pupillary diameter and surgery time and ultrasound time. Methods: Prospective comparative study, carried out at the Center of Excellence in Ophthalmology, Brazil. We included 79 eyes of 67 patients with nuclear opacity. The patients were divided into the control and study groups, including those who underwent cataract surgery with manual phacoemulsification, and femtosecond laser assisted cataract surgery, respectively. All surgeries were performed by the same experienced surgeon. All patients received topical non-steroidal anti-inflammatory drugs on the day before surgery and the same mydriatic eye drops preoperatively. To quantify pupillary size, measurements were performed using a surgical compass: anterior to the phacoemulsification procedure and at the end of the surgery. In the study group, measurements after laser were added. Surgical time and phacoemulsification time were also analyzed. Results: No significant difference was found between the pre-femto × pre-phaco pupil size (8.69 ± 0.44 mm × 8.63 ± 0.72 mm; p=0.643), and the pupil size at the end of surgery (7.96 ± 0.98 mm × 7.78 ± 0.95 mm; p=0.480) and the mean time of surgery (p=0.780). However, in the femtosecond laser assisted cataract surgery group, a transient increase in pupillary diameter after laser treatment was observed, indicating a tendency for greater variation in the femto group. Conclusions: Although pupil size diameter was similar at the end of surgery, the femtosecond laser assisted cataract surgery group presented higher intraoperative pupil variation. The surgeon should be aware of pupil size diameter before surgery for better and safer performance of femtosecond laser assisted cataract surgery.

A Comparative Cohort Study of Visual Outcomes in Femtosecond Laser-Assisted versus Phacoemulsification Cataract Surgery

To evaluate visual outcomes after femtosecond laser-assisted cataract surgery (LCS) with phacoemulsification cataract surgery (PCS). Prospective, multicenter, comparative case series. Consecutive patients undergoing femtosecond LCS or PCS with intraocular lens insertion. A total of 1876 eyes of 1238 patients (422 male and 772 female) who underwent cataract surgery between January 2012 and June 2014 were included in the study: 1017 eyes from center A and 859 eyes from center B. Cases underwent clinico-socioeconomic selection. Patients with absolute LCS contraindications were assigned to PCS; otherwise, all patients were offered LCS and elected on the basis of their decision to pay (the out-of-pocket cost for LCS). Demographic and postoperative data were collected to determine differences between groups. Six-month postoperative visual and refractive outcomes. Masked subjective refractions were performed 2 to 6 months postoperatively. There were 988 eyes in the LCS group and 888 eyes in the PCS group. Baseline best-corrected visual acuity (BCVA) was better in LCS compared with PCS (20/44.0 vs. 20/51.5; P < 0.0003). Preoperative surgical refractive aim differed significantly between groups (LCS -0.28 vs. PCS -0.23; P < 0.0001). More patients who received LCS had Toric lenses implanted compared with PCS (47.4% vs. 34.8%; P < 0.0001). Postoperative BCVA was better after LCS (20/24.5 vs. 20/26.4; P = 0.0003) with a greater proportion of LCS cases achieving BCVA >20/30 (LCS 89.7% vs. PCS 84.2%; P = 0.0006) and 20/40 (LCS 96.6% vs. PCS 93.9%; P = 0.0077). However, PCS cases had more letters gained compared with LCS cases (13.5 vs. 12.5 letters; P = 0.0088), reflecting baseline BCVA differences. Mean absolute error was higher in LCS compared with PCS (0.41 diopters [D] vs. 0.35 D; P < 0.0011). The percentage of eyes within 0.5 D of error from preoperative aim refraction was higher in the PCS group (LCS 72.2% vs. PCS 82.6%; P < 0.0001). Femtosecond LCS did not demonstrate clinically meaningful improvements in visual outcomes over conventional PCS.